This invention relates to an apparatus and method useful in foundry operations for detecting the misalignment of cooperating sand mold sections. Particularly, this invention relates to the use of a non-contact distance measuring device, located adjacent to the path of travel of the mold sections, to detect the misalignment of the internal cavities of the mold sections.
Typically, in foundry operations, sand mold sections must remain aligned in order to produce a correctly formed molded article when the mold cavity is filled. If the mold sections should become misaligned due to difficulties in the formation of the mold sections, or in the transporting or filling processes, the end product will be improperly formed and unuseable. The problem in detecting this misalignment is that the cooperating mold sections typically give no outward visual indication of misalignment as they are advanced from the mold making machine to the mold pouring station, even when in actuality the internal mold cavities may be misaligned. The only way to currently detect any misalignment of the mold cavity is to wait and check the molded end product for any alignment errors, and this delay in finding an error often results in a great and expensive waste, inasmuch as the end product can only be checked after a number of mold sections, all possibly misaligned, have been filled and transported to the end of the foundry production line. The present invention eliminates the necessity of waiting until the end of the production line and the possible waste by determining, while the mold section advances both to and from the mold pouring station, whether the hidden internal mold cavity is aligned properly by employing a non-contact distance measuring device to detect the misalignment.
Non-contact distance measuring devices such as devices utilizing lasers, have been employed in a variety of manufacturing and industrial applications. Laser measuring devices, for example, have been used for such diverse applications as measuring fluid levels in bottles, performing quality control of machine parts, measuring the thickness of steel slabs, and numerous other areas wherein the flucuation of the distance to the surface of an object as it passes beneath a laser beam can be measured and correlated to a desired property or dimension of that article. Exemplary systems utilizing non-contact distance measuring devices in manufacturing applications are disclosed in U.S. Pat. No. 3,565,531 to Kane et al, U.S. Pat. No. 3,633,010 to Svetlichy, U.S. Pat. No. 4,375,921 to Morander and U.S. Pat. No. 4,453,083 to Bohlander et al. However, these systems have not utilized the distance measuring device in a foundry system to detect mold cavity misalignment.
It is, therefore, an object of the present invention to provide an apparatus and method for detecting mold section misalignment which employs a non-contact distance measuring device to detect the misalignment of internal mold cavities of the mold sections. Other objects and advantages of the invention will be particularly identified below.